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rans6andrew
27th Jan 2018, 17:21
A few months ago I made a lead box key holder a little bigger than a pack of 20 cigarettes to act as a Faraday cage in order to prevent my car keys in my tent from allowing access to my adjacent car. The box was made as two 5 faced rectangular trays which are a snug fit one inside the other. This proved to be quite effective at shielding the keys to my older "keyless go" car but I have found that it is not fully effective when used with my new car keys. The lead sheet used is a little over 1.5mm thick.

Would I have been better to make it of another metal sheet? Maybe copper?

I have tried putting the keys inside a posh Barley Sugar tin which is made of thinner steel sheet and this is less effective than the lead box.

What are the rules of thumb for this situation? Thickness? Conductivity of metal? Dimensions relative to wavelength? Moon phase?

Andrew.

UniFoxOs
27th Jan 2018, 18:06
Definitely better conductors will work better. Therefore copper is best, or aluminium if weight is an issue.

The important thing is to have no gaps through which the radiation can travel, and your one tray inside another approach should do this, but I'd still feel happier with finger-strips where the two parts meet. Maybe you could experiment a bit with kitchen foil - try more than one layer - apparently shoplifters line shopping bags with it to defeat the security devices on high-value goods.

Trossie
27th Jan 2018, 18:17
Definitely better conductors will work better.
... ... ...
Daniel Barenboim, Charles Mackerras, Thomas Beecham, Sir John Barbirolli, Claudio Abbado ... ?

Sorry! (Coat, hat ...)

VP959
27th Jan 2018, 18:19
Any good conductor will work well for the E part of the EM, but if you are going to be pretty close to the car, close enough that the M part may just be enough, then I'd suggest making the box from Mu Metal, as that will provide good magnetic as well as electrical screening. The snag is that Mu Metal is expensive.

If it were me then I'd just hunt around for a small tinplate box, like the ones you used to get small sweets in, and use that. A Minty's or Altoids tin would be ideal (both US products, so not easy to find here), if your fob will fit in it. As these tins are popular for electronic projects, you can buy blank ones, and there's at least one UK seller: https://thepihut.com/products/adafruit-altoids-gum-sized-tin

n5296s
27th Jan 2018, 18:33
The snag is that Mu Metal is expensive.
It's not THAT expensive in small quantities. The real problem, as I discovered after I'd bought some to screen some delicate electronics, is that to make it effective after construction you have to anneal it in hydrogen at something like 800C. Good luck doing THAT at home.

3FG
27th Jan 2018, 19:54
VP959's suggestion of a steel box is excellent. On a pedantic note, since the keyless fobs operate at 300-450MHz depending on locale, almost any metal with sufficient thickness to be mechanically strong will work, provided there are no gaps. The skin depth (or equivalently penetration depth) for e.g. Cu or Al is a few micrometers, so a few tens of micrometers thickness will attenuate the RF by more than 10000X. Ordinary steel is about 10X better than Cu, because it is ferromagnetic.

For electromagnetic shielding, there is little value in using mumetal at frequencies above a few hundred Hz, because practical thicknesses of steel are already effective. Lead is not a good choice, because it has little mechanical strength, and would be prone to gaps. Note that 4 layers of ordinary household Al foil would be sufficient.

Mr Optimistic
27th Jan 2018, 20:41
Reckon gaps no bigger than 0.1lambda and good bonding, remembering skin effect and poor joints give junction effects and non-linearities which generate harmonics.

vapilot2004
27th Jan 2018, 20:58
A mate that does quite a bit of camping and traveling about in his modern car uses a Band-Aid tin. These things are made out of steel.

Uncoated lead may not be the best of metals as you may want to wash your hands after handling it.

Gertrude the Wombat
27th Jan 2018, 21:01
Given the crapness of the radio comms of all the car keys I've ever had, I can't help wondering whether people may be over-thinking this? The original question was about being in a tent: if this is a tent in the UK it will be at least slightly damp, if it's not actually raining right now, and surely that's enough of a Faraday cage?

Gertrude the Wombat
27th Jan 2018, 21:48
Daniel Barenboim, Charles Mackerras, Thomas Beecham, Sir John Barbirolli, Claudio Abbado ... ?

Sorry! (Coat, hat ...)
Which reminds me of this one I haven't heard for a few decades, could just be new to younger readers here (are there any??) ...

Passenger puts one foot onto the platform of a bus. Conductor rings bell, bus pulls away, passenger falls underneath the following lorry, gets killed.

Company commiserates with the conductor for having witnessed such an unfortunate accident.

Next day, a second passenger puts one foot onto the platform of the bus. Conductor rings bell, bus pulls away, passenger falls underneath the following lorry, gets killed.

Company warns conductor that he really does have to be more careful.

Next day, a third passenger puts one foot onto the platform of the bus. Conductor rings bell, bus pulls away, passenger falls underneath the following lorry, gets killed.

This time the police take an interest, conductor is convicted of murder, and sentenced to the electric chair.

Executioner presses the button. Conductor just grins. WTF??

Executioner presses the button again. Conductor laughs out loud.

Executioner presses the button a third time. Conductor widdles himself laughing.

"WTF?" askes the executioner, well aware of the rule that after three failed attempts the prisoner goes free, "how did you survive that?"

"Easy peasy" comes the response: "I'm a bad conductor".

Pontius Navigator
27th Jan 2018, 22:20
VP, I tried selling some tobacco tins on eBay as either vintage artefacts or keysafe. Oddly no interest at all. They have gone to charity's.

Jetstream67
27th Jan 2018, 22:41
Actually the problem is that at UHF frequencies even a tiny 'slot' (couple of cm) where the lid and tin don't completely touch is enough to let the radio signal through and even make the outside of the tin a pretty efficient aerial. Professional 'box' designs use many flexible metal fingers to ensure perfect contact every few mm.

In the normal everyday world the pouch /pod solutions are still not 100% efficient but scrunching tin-foil tight round the keys works every time.

Sallyann1234
27th Jan 2018, 23:05
To be strictly accurate, the slot doesn't let the signal 'through' in the sense of it squeezing though the gap which will usually be only a tiny fraction of a wavelength.
What happens is that the circulating currents inside the cavity and on its surface meet a discontinuity at the slot, and the different potentials each side of the slot cause it to radiate. Although the contact fingers do block most of the gap, their significant function is to equate the potentials on each side to stop it radiating.
Slot antennas can be very useful when a low physical profile is required.

G-CPTN
27th Jan 2018, 23:13
Would a tin within a tin be more effective?

gemma10
27th Jan 2018, 23:22
Why not? You could market it as Tin Tin

Il Vero Padrino
27th Jan 2018, 23:32
I'm not an avionics person, but those I know use special bags for ESDS
(Electrostatic Discharge Sensitive) components, to protect the contents from unwanted radiation. I wonder if one of those would isolate the key fob ?

If so, you could line the box with the bag material, or just use the bag.

Avtrician
28th Jan 2018, 00:10
ESDS Bags dont protect against radiation, they are conductive so bleed any electrostatic charges away from the contents.

To shield your keys, wrap them in alfoil, and then put in a tin box. A Mylar bag may help as well.

cattletruck
28th Jan 2018, 00:46
Just drop your keys into the same glass of water as your dentures :}. This will also guarantee that your wonder of modern tech doesn't try to reverse park itself unaided at 3am in the morning.

:E

jolihokistix
28th Jan 2018, 01:34
Is it just an American thing, preferring Can-can to Tin-tin?

Terry Dactil
28th Jan 2018, 04:30
Can't you just disablethe the electronics in the car? Pull a fuse, find a secret switch or something, and then use the normal key.

My vehicle has a switch under the steering column to turn off the keyless entry system to prevent it draining the battery if the car is not to be used for an extended period. It is not obvious, not labeled, and you would not know it existed without a careful search of the owner's manual.

West Coast
28th Jan 2018, 07:08
Heard from others an old microwave with the cord cut off. No idea if it’s effective.

Avtrician
28th Jan 2018, 08:02
A good faraday cage also has a very good earth/ground connection otherwise induced voltages could be radiated.

ricardian
28th Jan 2018, 09:08
Why not? You could market it as Tin Tin

Or, as someone from Yorkshire would say when something is not in the tin
"Tin tin tin".

UniFoxOs
28th Jan 2018, 09:13
Heard from others an old microwave with the cord cut off. No idea if it’s effective.

Probably is, but a PITA when camping!

VP959
28th Jan 2018, 09:30
Old tobacco tins would be great for this, if you can find them. My late father made a lot of recordings on a Grundig battery powered reel-to-reel tape recorder in the early 1960's. We found lots of these small 3" reels of tape stored inside Players tobacco tins a couple of year ago and they were all in perfect condition. I sent them off to a chap who was able to recover the audio and put it all on CDs, and the sound quality, even though these tapes had been stored in a loft for around 40 years, was extremely good. It's a bit eerie hearing both your own voice (aged 11) and your father's voice more than 40 years after his death.

treadigraph
28th Jan 2018, 10:17
I've been slowly clearing my elderly aunt's garages and have filled a couple of dozen sacks with metal for recycling - yep, lots of old baccy tins and similar used for storing odds and ends by my late uncle, his brother and dad...

They appear to have thrown nothing out in the last sixty years...!

fujii
28th Jan 2018, 10:32
Amazon has quite a few types of key fob RF Blockers for sale at around $20 Australian, about 8.

Tom Cundall
28th Jan 2018, 11:25
Can't you just take the rotor arm out of the Distributor???? :E

PPRuNe Dispatcher
28th Jan 2018, 11:25
Many Mercedes-Benz keys can be completely turned off by pressing the lock button twice. The key light will flash for about one second to confirm the key has been turned off.

To turn it back on just press the unlock button.

PPD

UniFoxOs
28th Jan 2018, 11:32
The kind of car that has this sort of system will almost certainly not have a distributor.

But if the bloke that sold you the car bought you a drink, you could say you were taking the piss out of the Distributor.

yellowtriumph
28th Jan 2018, 12:12
Old tobacco tins would be great for this, if you can find them. My late father made a lot of recordings on a Grundig battery powered reel-to-reel tape recorder in the early 1960's. We found lots of these small 3" reels of tape stored inside Players tobacco tins a couple of year ago and they were all in perfect condition. I sent them off to a chap who was able to recover the audio and put it all on CDs, and the sound quality, even though these tapes had been stored in a loft for around 40 years, was extremely good. It's a bit eerie hearing both your own voice (aged 11) and your father's voice more than 40 years after his death.

I'm doing something sort of something similar. This year's winter project is to transfer all the audio tapes I recorded in the early 70's to the PC. I'm doing it using my original Akai tape recorder that hadn't seen mains electricity since that time and has been stored in the loft - it works perfectly, just like it was yesterday which came as a surprise to me I can say.

Some of the tapes play very well, some not so much. They changed the formulation of the tapes a lot and some of them are/were prone to moisture absorption which can make them very difficult to 'drag' over the rollers and guides. Keeping your tapes in airtight tins has probably helped with slowing that process down. The thinner the tape the more likely the problem. But slowly and surely I am transferring them with the help of putting them in the oven at 60 deg centigrade for 4 or 5 hours and if needs be holding a cotton swab soaked in a very liquid car polish against the back of the tape as it comes off the supply reel!

As you say, funny to hear yourself as you were 40+ years ago! Mostly Radio broadcasts of the era - 'Sounds of the Seventies', I'm sorry I'll read that again. Good times.

Uplinker
28th Jan 2018, 12:34
So if I understand this correctly, the type of key you are talking about works by its proximity to the car, and when it is close enough, it unlocks the car - is that right? I have not heard of these.

If so, your tobacco box solution should work, but attach an earth strap between the lid and the body of the box - the hinges do not always make good contact, and this is probably why your other solutions have not worked. The whole box needs to be electrically connected.

I had an old Golf car once and everytime I drove under a bridge, the longwave radio - during the temporary absence of the transmitter signal - would pick up the ignition system, giving rise to a very loud buzz from the speakers. Odd, I thought, the bonnet is metal and the hinges are metal to metal; why is the interference getting out? Anyway, I bolted a piece of earth strap between the bonnet and the car chassis, near one of the hinges, and the problem was completely cured.

VP959
28th Jan 2018, 13:35
I'm doing something sort of something similar. This year's winter project is to transfer all the audio tapes I recorded in the early 70's to the PC. I'm doing it using my original Akai tape recorder that hadn't seen mains electricity since that time and has been stored in the loft - it works perfectly, just like it was yesterday which came as a surprise to me I can say.

Some of the tapes play very well, some not so much. They changed the formulation of the tapes a lot and some of them are/were prone to moisture absorption which can make them very difficult to 'drag' over the rollers and guides. Keeping your tapes in airtight tins has probably helped with slowing that process down. The thinner the tape the more likely the problem. But slowly and surely I am transferring them with the help of putting them in the oven at 60 deg centigrade for 4 or 5 hours and if needs be holding a cotton swab soaked in a very liquid car polish against the back of the tape as it comes off the supply reel!

As you say, funny to hear yourself as you were 40+ years ago! Mostly Radio broadcasts of the era - 'Sounds of the Seventies', I'm sorry I'll read that again. Good times.


Good luck with the process. I did hunt around for a reel-to-reel tape recorder, but in the end just paid a reasonable fee to this chap: Precious Voices Transfer Tape to CD - Audio Services (http://www.preciousvoices.co.uk/) who I'd highly recommend. He tries his best to remove any noise from the recordings, too, and seems to do a very good job at it.

There's one recording from 1963 of me reading the lesson at the school Harvest Festival (although catholic, I went to a CofE primary school - made life interesting.....). My father recorded an introduction, in his best "BBC English" voice, and hearing me trying desperately not to fluff any lines is almost painful, as I can remember all the other children looking at me and I was sure some were just willing me to cock it up.

Pontius Navigator
28th Jan 2018, 13:38
Uplinked, my Gold Flake had no hinge. I was surprised there was no interest in them.

Uplinker
28th Jan 2018, 13:55
I don’t know them; did they just have fit-on lids?

If so, the same problem of poor electrical connection would apply and an earth strap would cure :ok:




..........putting them [audio tapes] in the oven at 60 deg centigrade for 4 or 5 hours....... my bold.

Really? That sounds way too hot - the tape might get physically damaged !! Be careful.

VP959
28th Jan 2018, 14:16
I've just dug out one of my 40 to 45 year old Players tobacco tins. These are tin plated mild steel, with some sort of pale gold colouring originally (there are signs of rust on the outside) and a shiny tin surface internally. The lids are a very tight fit and have a moulded in rubber seal around the inside. There are slots at the corners to insert a coin to prise the lid off, they fit that tightly. There are two raised dimples on either side of the base that project out and lock the lid down tightly when it's fitted.

A quick continuity check shows that the lid is very well electrically connected to the base, even after all these years. I have absolutely no doubt that a tin like this would work perfectly well as a screened enclosure for the sort of very low level RF signal transmitted by the car (and it's the car transmission that needs to be blocked from getting to the key transponder, primarily).

I'll go and do a practical test with my Prius fob and report back in a few minutes.

Edited to add:

OK, I put the Prius fob inside the tin and closed the lid. It's easy to tell when the car detects the fob as it turns on the interior lights. Holding the tin in my hand, the car detected the fob when it was about 18" from the front door handle transmitter (the Prius has three door handle transmitters, both front doors plus the rear hatch). It failed to detect the fob with it inside the tin held in my hand from the rear hatch transmitter, even when it was toughing the bodywork (not sure where the antenna in the car is).

I then put the tin on the ground and gradually pushed it towards the car with my foot. I couldn't get it to detect the fob at all. I suspect that holding the tin in my hand may well have aided the signal getting through.

For reference, normally the fob is detected at a distance of around 8 to 10 ft from the car, perhaps a bit further than this if the fob is in my hand, rather than in a pocket.

From this quick and dirty test I would conclude that an early 1960's vintage Players Navy Cut tobacco tin, in poor condition, with signs of external corrosion, would be perfectly OK as a fob screen when camping near the car, particularly if left on the ground, rather than held in the hand.

Gertrude the Wombat
28th Jan 2018, 14:26
I did hunt around for a reel-to-reel tape recorder
As far as I know I've got one in the attic. Hasn't been used for a few decades, but it worked last time it was used.

yellowtriumph
28th Jan 2018, 14:27
I don’t know them; did they just have fit-on lids?

If so, the same problem of poor electrical connection would apply and an earth strap would cure :ok:



my bold.

Really? That sounds way too hot - the tape might get physically damaged !! Be careful.

I did a lot of www research on it before putting the first one in, and I used a professional thermocouple temperature meter to monitor the temperature rather than relying on the knob on the front of the oven!

I was slightly worried about electromagnetic fields wafting around inside the oven close to the tapes so naturally I tried it first with a tape I knew had nothing of value on it. It did not seem to harm the tape at all. Some other tapes I have left in the airing cupboard for a good few weeks just to see and I have yet to try them.

I probably have dozens and dozens of hours of material so it is a slow process, but one I am enjoying. I am using an audio editing package called 'Audacity' to edit down the material and to clean it up of background noise etc, making true mono excerpts of otherwise single track stereo recordings,. It's an amazing piece of free software. Simply amazing.

VP959
28th Jan 2018, 14:31
As far as I know I've got one in the attic. Hasn't been used for a few decades, but it worked last time it was used.

Thanks, A pity I didn't think to ask on here - I should have guessed that someone here would have one!

This place really is a gold mine for information at times.

Pontius Navigator
28th Jan 2018, 14:44
VP, of course to keep tobacco fresh the tins have to be air tight. There are hinged lids of course, State Express was one and tin Players Navy Cut which were more like a cigarette case another.

Of course in the day these time only lasted a day or so as 40-50 cigsvca day was not unknown.

Another, I have a photo of my father with one, was a round players tin. IIRC it had something on the lid, possible to cut the foil seal.

G-CPTN
28th Jan 2018, 14:47
it had something on the lid, possible to cut the foil seal.

:ok: . . . . .

VP959
28th Jan 2018, 14:55
VP, of course to keep tobacco fresh the tins have to be air tight. There are hinged lids of course, State Express was one and tin Players Navy Cut which were more like a cigarette case another.

Of course in the day these time only lasted a day or so as 40-50 cigsvca day was not unknown.

Another, I have a photo of my father with one, was a round players tin. IIRC it had something on the lid, possible to cut the foil seal.

The tin I've just tested (in the edited post above with the results) was a Players Navy Cut rectangular one, with no hinge. It's about 4 1/4" long, an inch deep and about 3 1/4" wide. It looks to have been a pale gold colour with a red sign in the centre of the lid, with the words "RUBBED READY FOR SMOKING" at the bottom.

It's now pretty easy to get the lid off, but I would imagine that when sold it may have been very airtight and one would have needed to put a penny (the old big one) in one of the corner slots to price the lid off.

Anyway, it worked well enough at screening my Prius fob, even in it's aged and rather poor condition.

Pontius Navigator
28th Jan 2018, 18:54
VP, better save up for new Prius then.

megan
28th Jan 2018, 21:45
Know nothing of their efficacy.

https://www.ebay.com.au/itm/Faraday-Key-Fob-Protector-Australian-Stock-Dont-Lose-your-car-to-Thieves-/142570635952?_trksid=p2385738.m4383.l4275.c10

Terry Dactil
29th Jan 2018, 00:31
I'll go and do a practical test with my Prius fob and report back in a few minutes.
If you own a Prius then you don't have that problem anyway.
The cunning Japanese have already thought of this and provided a built-in solution.
If you lock your car and the key remains in range for more than 10 minutes, the system automaticqally shuts down.
If you are realyy paranoid, you can switch off the system manually.
There is no need to faff about with Faraday cages and tobacco tins, just RTFM. :ok:
https://www.pprune.org/attachment.php?attachmentid=4052&stc=1&d=1517185654

jolihokistix
29th Jan 2018, 01:20
A small spanner.


(Disconnect one of the battery leads. Only takes a minute, but you may have to reset your clock afterwards.)

ian16th
29th Jan 2018, 08:20
A small spanner.


(Disconnect one of the battery leads. Only takes a minute, but you may have to reset your clock afterwards.)

Plus such things as window one touch function, radio pre-sets, and electric seat memory positions.

The list can get rather irritatingly long on modern cars.

VP959
29th Jan 2018, 09:26
If you own a Prius then you don't have that problem anyway.
The cunning Japanese have already thought of this and provided a built-in solution.
If you lock your car and the key remains in range for more than 10 minutes, the system automaticqally shuts down.
If you are realyy paranoid, you can switch off the system manually.
There is no need to faff about with Faraday cages and tobacco tins, just RTFM. :ok:
https://www.pprune.org/attachment.php?attachmentid=4052&stc=1&d=1517185654

The OP does not own a Prius. I do.

My test was for his benefit, using my Prius to test a tobacco tin as a fob screening container, simply because my Prius has a similar keyless entry system to the car the OP owns.

It pays to read the thread from the start, sometimes.................

PS: FWIW, I've owned a Prius since 2005, several different models, and have read every single manual from cover to cover, so telling me to read the manual was not really required. I've also got copies of all the TSBs for my current model, as well, and I've got a CANBUS reader and have reprogrammed a few of the car's settings, so probably know a reasonable bit about how the car works.

VP959
29th Jan 2018, 09:36
Plus such things as window one touch function, radio pre-sets, and electric seat memory positions.

The list can get rather irritatingly long on modern cars.

Disconnecting the battery causes so much pain and grief in terms of reprogramming afterwards, that some cars come with a system to maintain the 12V battery supply when doing it. Mine does, you connect a supplementary supply to two terminals that are provided for the purpose under a small cover under the bonnet. You then disconnect the 12V battery (with care, putting temporary insulating sleeves over the connectors as you remove them), fit the new 12V battery, then carefully remove the temporary insulating sleeves and refit the leads to the battery, +ve first, then the ground lead. You can then remove the temporary supply, close the cover and bonnet and all the settings will remain as they were.

I would imagine that you could adapt this procedure for any other car that loses a lot of settings when the 12V battery is disconnected.

Uplinker
29th Jan 2018, 10:55
I did a lot of www research on it before putting the first one in, and I used a professional thermocouple temperature meter to monitor the temperature rather than relying on the knob on the front of the oven!

Fair enough, it obviously works, but still sounds bloody hot to me :)

Airing cupboard, or even just a room in a centrally heated home for a week should gently dry stuff out I would have thought? Our washed clothes become bone dry in a couple of days hanging on a clothes horse in the spare bedroom.

Pontius Navigator
29th Jan 2018, 11:08
A small spanner.


(Disconnect one of the battery leads. Only takes a minute, but you may have to reset your clock afterwards.)

In my car it is a simple job. Empty boot, remove 6/7 seats, remove lower trim and expose battery. Disconnect terminal, reload boot. Lock car.

Oops, central locking didn't work.

jolihokistix
29th Jan 2018, 11:34
Plus such things as window one touch function, radio pre-sets, and electric seat memory positions.

The list can get rather irritatingly long on modern cars.


Touche'. Still, the question was about going on a camping trip and not getting the car stolen. How important is the car? How many times a year? How precise does this Faraday cage have to be? Why can't we just buy one on the net? :ugh:


Give me my little spanner any day. I have had about 35 cars in my short life, but never a modern one with pre-set switches. Well, I lie, but the pre-settings did not really bother me too much.


Over the years I have also lost count of the number of times I've disconnected the battery before going on long trips. Battery life was extended, (the tricklectrics did not cause it to run down), and even after three months the car always started first time.


I do however concede that if presettings are as important as the clock, and you drive a Duck like Pontius N, then sometimes things are not so simple.

VP959
29th Jan 2018, 11:46
12V battery life when the car isn't used for an extended period caught me out badly with my first Prius. We'd been on holiday for three weeks and left the car in a long stay car park at Gatwick. On our return, the car wouldn't unlock, so I had to use the emergency key, as soon as I opened the door the alarm went off, albeit a bit quietly, and I couldn't get it to stop. What was worse was that I couldn't open the tail gate to get at the 12V battery to disconnect it and stop the alarm, as that had an electric lock and wouldn't open, and there was no way of opening it from inside.

We had to call out Brittania Rescue who put enough charge into the 12V battery, via the terminals that are available in a small box under the bonnet, to boot up the car and allow the inverter to power up and thus charge the 12V battery from the main hybrid battery (the Prius doesn't have a starter motor - everything is run from the HV supply from the hybrid battery when it's turned on).

Other Prius owners have found the same. When new the car is OK for around a month without being used, but this drops as the small 12V battery loses capacity with age. It's probably one of the biggest nuisance factors with the car, which I've been told has been fixed with the model I now have (I've not left it long enough to test this out yet). As a way around the problem I found that a small 3 cell model aircraft LiPo battery, with the right terminals to fit the emergency 12V "boot up" connections, will do the job. It needs a diode in series to prevent the car inverter from trying to charge it once the car has booted up, but that's all. I've found that the 5Ah 3 cell pack I made up seems to have a long shelf life, and only needs a top up charge once a year or so when not used.

yellowtriumph
29th Jan 2018, 12:00
Fair enough, it obviously works, but still sounds bloody hot to me :)

Airing cupboard, or even just a room in a centrally heated home for a week should gently dry stuff out I would have thought? Our washed clothes become bone dry in a couple of days hanging on a clothes horse in the spare bedroom.

I wouldn't disagree in principle, you'll note I said I had indeed placed some tapes in the airing cupboard to see how they go. I haven't had time to try them yet.

gemma10
29th Jan 2018, 13:13
In my car it is a simple job. Empty boot, remove 6/7 seats, remove lower trim and expose battery. Disconnect terminal, reload boot. Lock car.

Oops, central locking didn't work.

Almost as bad as trying to replace a headlamp bulb in a Clio. :ugh:

MurphyWasRight
29th Jan 2018, 15:54
Over the years I have also lost count of the number of times I've disconnected the battery before going on long trips. Battery life was extended, (the tricklectrics did not cause it to run down), and even after three months the car always started first time.


I do however concede that if presettings are as important as the clock, and you drive a Duck like Pontius N, then sometimes things are not so simple.

Have to admit first time I read this I was wondering why/how disconnecting the battery before a 'long trip' in the car would work :O

One other fun thing that (at least used to) happen with some cars on battery disconnection was activating an anti-theft feature in the radio; if you had never set/or forgot a code the radio could only be revived by a dealer who would charge $100 or so since it required a serial # on back of radio so they would flat rate remove/install radio as well as the reset itself.

PDR1
29th Jan 2018, 16:12
I do however concede that if presettings are as important as the clock, and you drive a Duck like Pontius N, then sometimes things are not so simple.

If you drive a duck you must expect a larger bill.

PDR

jolihokistix
29th Jan 2018, 23:19
If you drive a duck you must expect a larger bill.

PDR
Sometimes the cheapest option is to be found on the web.

visibility3miles
30th Jan 2018, 00:12
Grounded copper wire mesh everywhere.

If you can't get cell phone service within your cage, you know you've succeeded.

As to keeping your car off the airwaves, take it up with the dealer or manufacturer, and innocently ask, "How do they do that?" Then block that.

Or threaten to sue.

ian16th
30th Jan 2018, 09:09
Don't shoot the messenger. (https://mybroadband.co.za/news/security/246357-putting-a-smartphone-in-a-tinfoil-shoebox.html)

I just came across this on a local website.

It appears that biscuit tins came out as best bet.